FIGURE 5.

Detection of H&E(–) lymph nodes of patients with stage III CC harboring aggressive tumor cells, as indicated by KLK6 mRNA, is increased when RNA is extracted from half a lymph node compared with a few tissue sections. Expression levels of CEACAM5 (red bars), KLK6 (blue bars), and SLC35D3 (green bars) mRNA in 2 to 4 LNs (LN1–LN4) of 3 patients with stage III disease. Each LN was evaluated for the presence (H&E(+)) or absence (H&E(–)) of disseminated tumor cells by microscopic examination of H&E-stained tissue sections and analyzed for mRNA expression levels in RNA extracted from 80-µm sections adjacent to the section for H&E examination (80 µm) and in RNA extracted from the entire other half of the LN (Other half). Amounts of mRNA and 18S rRNA were determined by multiplex qRT-PCR and results are given as (mRNA copies/18S rRNA copy) × 10¹². Short bars, below the 10 tick indicate no detection of the mRNA. CC = colon cancer; H&E = hematoxylin-eosin; LN = lymph node; qRT-PCR = quantitative reverse transcription polymerase chain reaction.